Bo Xu

Environmentally benign scintillators with broadband radioluminescence are highly desirable for low‐cost, high‐performance x‐ray imaging. Recently, copper iodide (Cu–I) clusters have emerged as promising candidates, owing to strong spin‐orbit coupling, favorable solution processability, excellent x‐ray absorption efficiency, and efficient exciton harvesting enabled by aggregation‐induced emission and thermally activated delayed fluorescence. However, the mechanism by which aggregation‐state variation enhances the light yield by modulating intermolecular interactions remains poorly understood. Here, we establish a pair of isomeric Cu–I clusters with nearly identical x‐ray attenuation coefficients as a model platform to isolate and elucidate the role of intermolecular coupling. In this context, we uncover a breakthrough mechanistic picture in which engineered excited‐state coupling accelerates carrier relaxation and promotes efficient exciton harvesting and radiative recombination. Guided by this mechanism, water‐resistant cluster scintillator glasses with excellent processing flexibility are fabricated, delivering a high light yield of 32,456 photons MeV ⁻¹ and spatial resolution of 33.6 lp mm ⁻¹ . Furthermore, tandem integration with a high‐Z scintillator enables selective density‐discriminating x‐ray imaging and micro‐computed tomography. This work provides mechanistic guidance for ligand engineering in the design of efficient cluster scintillators and facilitates the high‐throughput development of promising metal‐cluster complexes for advanced optoelectronic applications.

I–III–VI quantum dots (QDs) are premier candidates for next-generation lighting and display technologies due to their low toxicity, wide color tunability, and high photoluminescence quantum yields (PLQYs).

Interface engineering has emerged as a critical strategy for advancing perovskite light-emitting diodes (PeLEDs), enabling remarkable improvements in the device efficiency, stability, and spectral purity. This Review provides a comprehensive overview of interface engineering in PeLEDs, beginning with the fundamental principles that govern carrier injection, transport, and recombination at heterojunctions between perovskite emitters and charge-transport layers. We then survey advanced characterization techniques, including photoelectron spectroscopy, scanning probe microscopy, and time-resolved optical methods, that elucidate interfacial energy-level alignment, defect states, charge dynamics, and degradation pathways. On the basis of these insights, we systematically discuss versatile engineering strategies, such as self-assembled monolayers, dipole interlayers, dimensional regulation, and passivation schemes, to mitigate non-radiative recombination, balance charge fluxes, and enhance operational stability. Finally, we highlight emerging applications spanning high-resolution displays, flexible lighting, and lasing while outlining key challenges and future directions toward commercial realization. This Review aims to offer a holistic framework linking interfacial design to device performance, guiding next-generation PeLED development.

The anchoring group of self‐assembled monolayer (SAM) hole‐transporting materials dictates both substrate binding and interfacial passivation, serving as a key lever for high‐performance perovskite photovoltaics. Herein, we report a novel SAM molecular material, denoted by XS21 , engineered with a multidentate dipicolinic acid (DPA) anchoring core to address conventional adhesion and degradation limitations. From an experimental perspective, the DPA anchor is found to promote molecular chemisorption onto the substrate, potentially originating from the dual‐action mechanism of pyridine–Ni coordination coupled with dicarboxylate‐metal interaction. Furthermore, XS21 imparts both low acid‐dissociation constants ( K _a ) and superior ultraviolet (UV) photostability. Consequently, wide‐bandgap (1.79 eV) perovskite solar cells containing XS21 deliver a champion power conversion efficiency (PCE) of 21.54% with an exceptional open‐circuit voltage of 1.372 V. Crucially, integrating XS21 into monolithic all‐perovskite tandem solar cells yields a remarkable PCE of 29.62%, alongside an outstanding operational stability (retaining >90% of initial efficiency after 900 h of continuous operation). This work establishes multi‐dentate pyridine‐carboxylate anchoring as a vital paradigm for next‐generation efficient and stable perovskite photovoltaics.

The practical deployment of perovskite solar cells (PSCs) is critically hindered by their susceptibility to moisture, oxygen, and thermal degradation, particularly under high‐temperature and high‐humidity conditions. Herein, we design and synthesize a dicarbonyl‐functionalized thienoacene passivator featuring multiple Lewis basic sites and medium‐length heptyl chains. This molecule exhibits exceptional thermal stability and anchors robustly at perovskite grain boundaries via multidentate Pb─O and Pb─S coordination bonds, effectively relieving interfacial tensile strain, passivating electronic defects, and enhancing the thermal integrity of the perovskite lattice. The hydrophobic heptyl chains further impart superior moisture resistance, while the π ‐conjugated backbone facilitates efficient charge transfer at the perovskite/hole‐transport layer interface. As a result, the target devices achieve a champion power conversion efficiency of 25.02% for lab‐scale cells and 23.34% for 1.0 cm ² devices. Notably, the unencapsulated devices retain over 82% of their initial efficiency after 1000 h of continuous illumination at 85°C under an inert atmosphere. This work establishes multidentate surface passivation and strain management as a highly effective strategy for realizing efficient and operationally stable perovskite photovoltaics.

Co‐deposited strategy of self‐assembled molecule (SAM) and perovskite could simplify the fabrication process as well as achieving the high‐performance solar cells. However, the correlative mechanism between molecular structures, film crystallization kinetics, and device properties is not clearly identified. Herein, referring to representative carbazole‐phosphoric acid molecules, we introduced a π‐conjugation extended carbazole of (2‐(12‐phenylindolo[2,3‐a]carbazol‐11(12H)‐yl)ethyl)phosphonic acid (named by SAM‐XS22). The XS22 additive with larger steric hindrance could improve the perovskite crystallinity as well as the reduced peak intensity of excess PbI ₂ and accelerate the interfacial carrier extraction/transfer due to the heterogeneous SAM distribution within bulk film. As a result, we achieved the champion power conversion efficiency of ∼20.72% for 1.78‐eV FA _0.83 Cs _0.17 Pb(I _0.6 Br _0.4 ) ₃ wide‐bandgap perovskite solar cells, which can also remain > 90% retention over 600 hours of maximum‐power‐point tracking.

Control over crystallization pathways and halide distribution is essential for realizing efficient and stable wide-bandgap (WBG) perovskite solar cells (PSCs), yet most advances rely on additives while the intrinsic role of precursor stoichiometry remains insufficiently understood. Here we show that precursor stoichiometry, specifically the balance between FAX and PbX₂ (X = I, Br), serves as an additive-free chemical lever that regulates precursor supersaturation and nucleation kinetics, thereby directing crystallization and halide homogenization in FA_0.83Cs_0.17Pb(I_xBr_1-x)₃ perovskites. We identify a stoichiometric regime with a PbI₂-to-total PbX₂ ratio of ∼55-75% that minimizes supersaturation, increases nucleation energy barrier, and slows crystal formation, yielding perovskite films with full coverage, preferred crystallographic orientation, and reduced residual strain. The optimized chemistry enables efficient and photostable WBG PSCs across a broad bandgap range (∼1.67, 1.79, 1.85, and 1.93 eV), achieving champion power conversion efficiencies of ∼24.19%, 21.64%, 19.98%, and 16.83%, respectively. Furthermore, this strategy enables monolithic all-perovskite tandem solar cells that deliver ∼29.10% efficiency with >80% retention over 400 h of maximum-power-point tracking. By establishing mechanistic links between precursor stoichiometry, crystallization pathway, electronic homogeneity, and device stability, this work provides a rational and broadly applicable chemical framework for advancing WBG perovskites in single-junction and tandem photovoltaics.

Vapor‐deposited light‐emitting diodes (LEDs) based on non‐toxic copper‐iodide nanoclusters (Cu NCs) hold immense potential for scalable solid‐state lighting and displays. However, interface defects‐induced device performance degradation remains a critical challenge for organic–inorganic nanoclusters. Here, we present an interfacial coordinate‐bond passivation strategy employing a pyridine‐functionalized self‐assembled monolayer (SAM) material featuring tailored pyridine anchoring groups. The designed pyridine‐functionalized SAM materials simultaneously passivate the Cu NCs emissive layer (EML) and optimize charge injections. Consequently, we demonstrate Cu NCs‐based LEDs achieving a peak external quantum efficiency (EQE) of 22.5%, a maximum luminance of 41 432 cd∙m ⁻² , and an improved operating half‐lifetime of 119 h at 1000 cd∙m ⁻² , which is among the best of reported vapor‐deposited clusters‐based LEDs. Moreover, we demonstrate active‐matrix displays by integrating Cu NCs‐based LEDs onto drive circuits. This work highlights the critical role of molecularly engineered SAMs in unlocking the high‐performance cluster‐based LEDs.